SHIFT+ENTER - > Puts semicolon at current line, creates and indents new line below.
ALT+ENTER - > Puts semicolon at current line, but keeps the cursor where it is.
Simple, useful.
This is a modification to an original work which was inserting extra carriage returns and would continue to add semicolons to lines that already had them. I also didn't like the shortcuts, so I updated to something that made more sense to me.
Based entirely on https://github.com/nechor/brackets-semicenter